原位碳、氮共掺杂二氧化钛空心球的制备与可见光光催化性能

Fabrication and Visible-Light Photocatalytic Activity of In situ Carbon and Nitrogen Co-Doped TiO_2 Hollow Sphere

在H2O2-HF的乙醇-水混合溶液中,通过水热处理碳氮化钛(TiCN)制备了碳、氮共掺杂TiO2空心球(CNTH).用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、X射线光电子能谱(XPS)和紫外-可见(UV-Vis)吸收光谱表征了所制备的样品.在可见光(λ≥400nm)照射下,通过降解甲基蓝检测了碳、氮共掺杂TiO2空心球的光催化活性.结果表明,源于TiCN中的部分碳和氮原子原位掺入了TiO2的晶格中,部分碳掺入TiO2点阵的间隙中.该材料在整个可见光区展示了增强的可见光吸收,其带边明显红移.光催化研究表明在强可见光吸收和独特的空心球结构的协同作用下,碳、氮共掺杂TiO2空心球展示了比P25更高的可见光光催化活性.

Carbon and nitrogen co-doped TiO2 hollow spheres （CNTHs） were synthesized by hydrothermal treatment of titanium carbonitride （TiCN） in a mixture of H2O2,HF,ethanol,and water.CNTHs were characterized by X-ray diffraction （XRD）,scanning electron microscopy （SEM）,transmission electron microscopy （SEM）,X-ray photoelectron spectroscopy （XPS）,and UV-visible （UV-Vis） diffuse reflectance spectroscopy.Some of the carbon and nitrogen from TiCN was doped into the lattice of TiO2 in situ,and some carbon atoms were incorporated into the interstitial positions of the TiO2 lattice.The CNTHs exhibited enhanced absorption over the whole visible-light region and an obvious red shift at the absorption edges compared with that of TiO2.The ability of the CNTHs to degrade methylene blue （MB） in aqueous solution under visible light irradiation （λ≥400 nm） was investigated.The CNTHs showed much higher photocatalytic activity than P25 in the degradation of MB because of the synergetic effects of their strong visible absorption and unique hollow sphere structure.